The present invention relates to a valve arrangement and, more particularly, to a valve arrangement for a plurality of hydraulic control valves of the type commonly designated as sub-plate mounted (SPM) valves.
Hydraulic fluid supply systems supply hydraulic fluid to the hydraulic actuators of various mechanical devices for the actuation of the devices. Undersea wells are one source for the recovery of certain petroleum products such as oil and gas and the operation of such undersea wells presents considerable maintenance and installation challenges. In such subsea or underwater well environments, hydraulic fluid supply or control systems are commonly provided to control a blow out preventer. The blow out preventer typically includes a number of valves having specialized functions and these valves frequently are actuated by valve operators which are capable of being controlled from a remote location through energization by a controllable actuation system.
One type of controllable actuating system is comprised of hydraulic control valves arranged in a subsea structure which incorporates various hydraulic valves and regulators, hydraulic connector systems, solenoid operated pilot valves, and electronic packages. One type of hydraulic control valve which may be comprised in the hydraulic control arrangement for a subsea structure such as a blow out preventer is referred to as a sub-plate mounted (SPM) valve. This type of valve is typically a hydraulically piloted control valve which controls the flow of hydraulic fluid to and from a subsea operator such as, for example, blow-out preventer rams or choke and kill valves.
One conventional arrangement for accommodating a number of valves such as sub-plate mounted (SPM) valves comprises a relatively large valve block having valve pockets machined therein each for receiving a valve and drilled galleries for fluid communication with the valves. One drawback of this conventional arrangement is that the large valve block is typically customized for its particular installation and is thus configured to accommodate a selected group of valves which may be of differing sizes. Accordingly, should the fluid handling requirements change, modification or redesign of the valve block may be relatively complex or cost-prohibitive. If a single block of metal is machined or bored to create the valve pockets and galleries, another disadvantage arises in that the entire valve block may need to be discarded even if the damage is limited to only a portion of the block such as, for example, damage to the retaining threads of a valve pocket or the threads of a port.